1001015-64-0Relevant academic research and scientific papers
A novel fluorogenic substrate for dinuclear Zn(II)-containing metallo-β-lactamases
Zhang, Yin-Lin,Xiao, Jian-Min,Feng, Ji-Li,Yang, Ke-Wu,Feng, Lei,Zhou, Li-Sheng,Crowder, Michael W.
, p. 1676 - 1679 (2013/04/10)
In an effort to prepare a fluorogenic substrate to be used in activity assays with metallo-β-lactamases, (6R,7R)-8-oxo-7-(2-oxo-2H-chromene-3- carboxamido)-3-((4-(2-oxo-2H-chromene-3-carboxamido)-phenylthio)methyl) -5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (CA) was synthesized and characterized. CA exhibited a fluorescence quantum yield (φ) of 0.0059, two fluorescence lifetimes of 3.63 × 10-10 and 5.38 × 10 -9 s, and fluorescence intensity that is concentration-dependent. Steady-state kinetic assays revealed that CA is a substrate for metallo-β-lactamases (MβLs) L1 and CcrA, exhibiting Km and kcat values of 18 μM and 5 s-1 and 11 μM and 17 s-1, respectively.
Novel fluorescent cephalosporins: Synthesis, antimicrobial activity and photodynamic inactivation of antibiotic resistant bacteria
Xiao, Jian-Min,Feng, Lei,Zhou, Li-Sheng,Gao, Hui-Zhou,Zhang, Yi-Lin,Yang, Ke-Wu
, p. 150 - 159 (2013/03/13)
Two novel fluorescent cephalosporins, TCA and TBCA, were synthesized and characterized by 1H NMR, 13C NMR, UV-vis, and fluorescence spectroscopies. Biological activity assays demonstrated that TCA inactivated a Klebsiella pneumonia strain that expressed extended-spectrum β-lactamases. Incubation of 6 μM TCA with K. pneumonia cultures resulted in cell death for 84% of the cells after 126 J/cm2 of light irradiation. In vitro, TCA exhibited a MIC = 0.5 μg/mL with Staphylococcus aureus. Kinetic evaluation revealed that TCA and TBCA were substrates for B1 and B3 subclass metallo-β-lactamases. TBCA exhibited stronger binding affinities to the Gram-positive bacterial strains MRSA1, MRSA2, and S. aureus with value of 2.95-6.59 μM per 108 cells/mL.
Synthesis of novel coumarin and benzocoumarin derivatives and their biological and photophysical studies
Abd-El-Aziz, Alaa S.,Mohamed, Hany M.,Mohammed, Shawkat,Zahid, Shamsulhaq,Ata, Athar,Bedair, Ahmed H.,El-Agrody, Ahmed M.,Harvey, Pierre D.
, p. 1287 - 1301 (2008/09/18)
(Chemical Equation Presented) Several derivatives of coumarin-3N- carboxamides (3-21) have been prepared via the reaction of the coumarin-3-carbonyl chloride (1) with a number of nucleophiles. Novel double-headed coumarin-3N-carboxamides (26-33) were also produced using the same method. The Pechmann-Duisberg reaction was applied to prepare new benzo[f]- benzo[h]coumarins and 4-(chloromethyl)-pyrano[3,2-c]coumarin-2-one (36-42). The reaction of 1-chloromethylbenzo[f]coumarins (36) with cyanide anion under different reaction conditions was also investigated in order to assess its suitability for nucleophilic substitution reactions as well as ring transformation products (43-49). Synthesis of 1-((benzo[d]thiazol-2-yl)methyl)- 9-hydroxybenzo[f]coumarin (50) represented the first example of methylene bridge-head heterocycle-containing benzo[f]coumarin. Some of the newly prepared coumarins exhibited anti-bacterial activity against Gram Positive and Gram negative bacteria. Compound 36d was found to be active against all the screened bacteria. Photophysical studies were performed on selected fluorescent benzo[f]- and benzo[h]coumarin and the quantum yields were also calculated. All new compounds were characterized by IR, MS, 1H and 13C NMR, as well as elemental analysis.
